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DTC C1A4A: Skid Control Buzzer Circuit: Procedure

WARNING: This page is about a different variant/trim than selected.
  1. PERFORM ACTIVE TEST USING TECHSTREAM (SKID CONTROL BUZZER) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus: Chassis / ABS/VSC/TRAC / Active Test / DSS Signal Buzzer.
    5. Perform the Active Test.
      ABS/VSC/TRAC

      Tester Display Test Part Control Range Diagnostic Note
      DSS Signal Buzzer Skid control buzzer Buzzer OFF or ON Buzzer can be heard

      OK

      Skid control buzzer sounds.

    NG → See step   8 

    OK: Go to next step 

  2. CHECK FOR DTCs (DTC C1A4A) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    4. Perform the following to make sure that the DTC detection conditions are met.

      HINT: 

      If the detection conditions are not met, the malfunction cannot be detected.

      1. Drive the vehicle at a speed for which radar cruise control operation is possible.
      2. Turn the cruise control switch (ON-OFF button).
      3. Push the cruise control switch to -/SET to begin control of vehicle speed using the cruise control system.
    5. Enter the following menus: Powertrain / Radar Cruise / Trouble Codes.
    6. Check for DTCs.

      Result

      Result Proceed to
      DTC is not output A
      DTC C1A4A is output B

    B → See step   3 

    A → See step   9 

  3. REPLACE DRIVING SUPPORT ECU ASSEMBLY 
    1. Replace the driving support ECU assembly. Refer to REMOVAL .

    NEXT: Go to next step 

  4. CHECK FOR DTCs (DTC C1A4A) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    4. Perform the following to make sure that the DTC detection conditions are met.

      HINT: 

      If the detection conditions are not met, the malfunction cannot be detected.

      1. Drive the vehicle at a speed for which radar cruise control operation is possible.
      2. Turn the cruise control system on using the cruise control switch (ON-OFF button).
      3. Push the cruise control switch to -/SET to begin control of vehicle speed using the cruise control system.
    5. Enter the following menus: Powertrain / Radar Cruise / Trouble Codes.
    6. Check for DTCs.

      Result

      Result Proceed to
      DTC is not output A
      DTC C1A4A is output B

    B → See step   5 

    A → END 

  5. REPLACE BRAKE BOOSTER WITH MASTER CYLINDER ASSEMBLY 
    1. Replace the brake booster with master cylinder assembly (skid control ECU). Refer to REMOVAL .

    NEXT: Go to next step 

  6. CHECK FOR DTCs (DTC C1A4A) 
    1. Connect the Techstream to the DLC3.
    2. Turn the power switch on (IG).
    3. Clear the DTCs. Refer to DTC CHECK / CLEAR .
    4. Perform the following to make sure that the DTC detection conditions are met.

      HINT: 

      If the detection conditions are not met, the malfunction cannot be detected.

      1. Drive the vehicle at a speed for which radar cruise control operation is possible.
      2. Turn the cruise control system on using the cruise control switch (ON-OFF button).
      3. Push the cruise control switch to -/SET to begin control of vehicle speed using the cruise control system.
    5. Enter the following menus: Powertrain / Radar Cruise / Trouble Codes.
    6. Check for DTCs.

      Result

      Result Proceed to
      DTC is not output A
      DTC C1A4A is output B

    B → See step   7 

    A → END 

  7. REPLACE POWER MANAGEMENT CONTROL ECU. Refer to  REMOVAL 
  8. GO TO ELECTRONICALLY CONTROLLED BRAKE SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING 
  9. USE SIMULATION METHOD TO CHECK. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING